Join us at the Salt and Water Stress GRC 2026 in beautiful Switzerland! The conference setting provides numerous opportunities for interactions with peers and high-profile researchers from diverse research fields. Registration: www.grc.org/salt-and-wat...
Look at the view from my room in winter 🤩

I am beyond thrilled (like the screaming and jumping type of thrilled) that my SNSF Starting Grant was funded. I will start my own lab @unibe.ch next year, studying succulent anatomy development and if and how this anatomy is required for efficient CAM photosynthesis in different Kalanchoë species 🌱

Together, we propose that much like in grasses, Kalanchoë MUTE makes stomatal subsidiary cells by delaying the guard cell program and inducing an asymmetric division program. 9/n

Finally, we used transcriptomics to detect the deregulated downstream genes when Kalanchoë MUTE is overexpressed. Unlike in Arabidopsis, genes linked to asymmetric divisions are upregulated and genes linked to guard cell differentiation are downregulated. 8/n

When overexpressing Kalanchoë MUTE, many additional subsidiary-cell-like cells were formed in Kalanchoë. This is strikingly different from the MUTE overexpression phenotype in Arabidopsis, where many additional guard cells pairs rather than subsidiary cells are formed. 6/n

Indeed, fluorescent reporter genes showed that both MUTE homologs are expressed specifically during the asymmetric divisions forming SCs. This suggested that MUTE might be involved in controlling SC divisions. 5/n

Gene-editing the two homologs of the core stomatal transcription factor MUTE disrupted stomatal formation and messed up asymmetric divisions - a first hint that Kalanchoë MUTE has a different role in leaf succulents than Arabidopsis. 4/n

10-day time-lapse imaging showed that young precursor cells undergo 6(!) rounds of asymmetric division oriented in a Fibonacci spiral. The first three divisions make non-stomatal cells before divisions 4 to 6 make the 3 subsidiary cells. Finally, a symmetric division makes the guard cell pair. 3/n

Unlike in Arabidopis, Kalanchoë stomata consist of two guard cells and three circularly arranged subsidiary cells. K+ staining of open and closed stomata shows that K+ is shuttled between the two stomatal cell types. Therefore, Kalanchoë’s subsidiary cells are likely functional helper cells. 2/n

This story was only possible through true team effort. Team Kalanchoë with Xin at the forefront. @jameshartwell.bsky.social, the most generous scientist who shared resources and answered countless questions. Read about MUTE during stomatal development in Kalanchoë www.biorxiv.org/content/10.1...

Finally made it to the bluer side on the first snowy day of the year ❄️